I’m over it

Why is it that guys just can’t take a relationship serious. Like you act like you actually want a relationship and things are going good until they start to see things turn serious and all of a sudden they either start being douche bags or they completely ignore you and act different towards you like as if they never felt anything towards you. Like thanks for making me catch feelings and then tell me you don’t want anything serious but you still want to be friends or friends with benefits. It honestly gives me no hope on finding some decent. I wonder if there mentally is like I’m feeling cute I might go break your heart and tell you I like you but as friends.